Taco 00 Series Circulator Pumps: Models and Selection Guide

The two hydraulic requirements for selecting a Taco 00 Series circulator are design flow (GPM) and system head loss (ft). Once those values are established, compare the required operating point with the applicable Taco pump curve, and then verify the construction materials, fluid type, temperature, working pressure, connection style, and electrical requirements.

It's not appropriate to select a circulator based only on its maximum GPM or maximum head. Taco's circulator-selection guidance recommends establishing the target flow and system head loss and then comparing that operating point with the available pump curves. Excessive oversizing should also be avoided.

The Taco 00 Series includes cartridge circulators for hydronic heating, radiant systems, hydro-air fan coils, chilled-water cooling, and domestic-water applications. The correct model depends on the hydraulic duty and the specific model configuration - not simply the application name.

How to select a Taco 00 Series Circulator

It's crucial to follow the sequence below to ensure the proper Taco 00 series model:

1. Determine the required design flow
   The water flow rate is the primary requirement when selecting the circulator, and it depends on the application load, design temperature difference, and other project variables. The result becomes the target flow rate in GPM.
2. Determine system head loss
   Must be calculated based on the design water flow rate. It must include the resistance of the piping and the applicable fittings, valves, heat exchangers, coils, boilers, and other components in that circuit. The resulting system head loss is expressed in feet of head.
3. Establish the target operating point
   To establish that, you must combine the required water flow rate and the calculated system pressure drop. With that in hand, you need to check the Taco literature to find the circulator model whose operating curve meets both parameters. For example, a system requiring 8 GPM at 8 ft of head needs a circulator whose performance curve can satisfy that point. A pump with a maximum flow above 8 GPM is not automatically suitable. Likewise, a pump with a shutoff head above 8 ft is not automatically suitable. The operating point must be evaluated on the pump curve.
   
4. Compare the operating point with the pump curve
   Plot the target GPM and head on the appropriate Taco circulator performance curve. Engineering best practices advise against choosing a circulator solely because its curve barely reaches the target point or because a larger pump offers significantly greater capacity. Where practical, the target point should fall in a reasonable operating region of the selected curve rather than at an end.
   
5. Verify the exact configuration required
   After identifying a hydraulically appropriate model, verify the configuration details below before ordering:

• Standard or IFC configuration
• Cast-iron, stainless-steel, or other available construction
• Connection type and size
• Supply voltage and other electrical requirements
• Allowable fluid temperature
• Maximum working pressure
• Mounting requirements

Note: Never assume that two versions of the same basic model have identical hydraulic performance. IFC versions can have different published flow/head performance compared to the corresponding standard circulator, per Taco technical documentation.

Taco 00 Series Overview

Taco 00 Series cartridge circulators use a direct-drive, self-lubricating design with no mechanical seal. Its design includes a replaceable cartridge that houses the primary moving components, allowing the circulator to be serviced without automatically replacing the entire pump assembly, a significant maintenance advantage.

The current Taco 00 Series covers a broad hydraulic range. The range goes up to 52 GPM flow and approximately 32 ft of head, although individual standard and IFC model performance varies and must be checked separately.

Taco 00 Series Model Comparison

The table below uses Taco's published technical data and performance data. These values describe the available performance range of each configuration; they are not a substitute for selecting from the actual pump curve at the required duty point, but can be useful for a quick check and circulator pre-selection.

Why these differences matter

The maximum values in the table should be used to narrow the candidate models - not to make the final selection.

For example, the 0010 and 0011 are not interchangeable simply because both can provide approximately 30 GPM. Taco currently publishes the standard 0010 at up to 32 GPM and 10 ft of head, while the 0011 reaches approximately 31 GPM and 31 ft of head. The 0011 is specifically intended for higher-head applications.

That difference can be critical where boilers, heat exchangers, coils, valves, or long piping circuits create significant pressure drop.

Standard vs. IFC Taco 00 Circulators

Taco offers many 00 Series models with an Integral Flow Check (IFC).

The IFC is incorporated into the circulator, eliminating the need for a separate in-line flow check. Its function is to help control unwanted gravity or reverse flow while simplifying installations in applications where a flow check is required.

As it's another element added to the system, pump performance will differ across the same models (as shown in the table above).

The built-in component affects the assembly's hydraulic characteristics. If the application uses an IFC model, perform the final selection against the IFC curve rather than the corresponding standard-model curve. This is particularly important when the required operating point is near the limit of a candidate circulator curve.

Cast Iron vs. Stainless Steel: Match Construction to the System

Circulator construction must be matched to the fluid and system type.

Taco 00 Series installation guidance distinguishes between cast-iron circulators for closed-loop systems and bronze or stainless-steel circulators for open-loop, fresh-water, or potable-water systems. Therefore, do not select a Taco 00 Series model for domestic or potable water service based solely on its hydraulic performance.

Verify that:

• The exact model is offered in suitable construction
• Taco approves that configuration for the intended fluid/application
• Temperature and working-pressure limits are acceptable
• The exact submittal and instruction sheet agree with the proposed installation

For example, the 0010 model current submittal identifies cast-iron and stainless-steel versions and states that the stainless-steel 0010 is intended for fresh-water systems.

Replaceable Cartridge Design

One useful service feature of the Taco 00 Series is the replaceable cartridge. Taco describes the cartridge as containing the circulator moving parts. If the appropriate replacement cartridge is available and the circulator body and other components remain serviceable, the cartridge can be replaced without automatically replacing the complete circulator.

Always match a replacement cartridge to the complete circulator product number and the current Taco replacement parts documentation. Taco specifically instructs technicians to confirm that the replacement cartridge corresponds to the full circulator product number.
That distinction prevents a serviceable design feature from being mistaken for universal cartridge interchangeability.

Common Taco 00 Series Selection Mistakes

Selecting from maximum GPM alone

Maximum GPM occurs at a different point on the curve from the conditions encountered in most operating systems. Always evaluate GPM and head together.

Selecting from maximum head alone

Maximum or shutoff head does not tell you how much flow the circulator will provide at the system actual resistance.

Treating standard and IFC versions as identical

The IFC version can have a different performance curve. Use the curve for the exact configuration being ordered.

Ignoring system material requirements

A hydraulically suitable cast-iron circulator is not automatically appropriate for an open-loop or potable-water application. Verify approved construction for the fluid and system.

Ignoring component pressure drop

Boilers, heat exchangers, fan coils, valves, and other components can contribute substantially to system head. Include them when establishing the design operating point.

Selecting from the model number alone

Model suffixes and configurations can change casing material, connection style, electrical characteristics, IFC status, and performance. Verify the full Taco model/submittal before purchase.

When is the Taco 00 Series the best choice for a pump circulator?

A Taco 00 Series circulator may be appropriate when the required operating point and application conditions fall within the published capabilities of a current 00 Series configuration.

The family includes options ranging from lower-flow residential circuits to higher-flow and higher-head residential/light-commercial applications, along with configurations for hydronic heating, radiant heating, hydro-air systems, chilled-water cooling, and domestic-water applications.

The important question is therefore not: “Which Taco 00 pump is best?”

It is: “Which Taco 00 configuration satisfies this system-required GPM and head while also meeting its fluid, material, connection, electrical, temperature, pressure, and control requirements?”

That is the basis for a defensible circulator selection.